The early Aryan invasions were vague and disjointed, although the people of north India today are defined as Aryans and those of the south as Dravidians. The Aryans came from the north from around 1500 BC and gradually spread across India from the Punjab and Sind (now in Pakistan) and down the Ganges towards Bengal.

The Rise of two great religions had their birth on the sub-continent - Buddhism and Hinduism. The Hindu religion is one of the oldest in the world. Even the priest-dominated Indus Valley civilization bears many similarities to Hinduism. The next era that India saw was that of the Vedic civilization. The earliest literary source that sheds light on India's past is the Rig Veda. It is difficult to date this work with any accuracy on the basis of tradition and ambiguous astronomical information contained in the hymns. The early Vedic age is historically dated to the second half of the second millennium BCE. Historically, after the collapse of the Indus Valley Civilisation, which occurred around 1900 BCE, groups of Indo-Aryan peoples migrated into north-western India and started to inhabit the northern Indus Valley. The Indo-Aryans represented a sub-group that diverged from other Indo-Iranian tribes at the Andronovo horizon before the middle of the 2nd millennium BCE. The Indo-Iranians originated in the Sintashta culture, from which arose the subsequent Andronovo horizon. The Indo-Aryans migrated through the adjacent Bactria–Margiana area (present-day northern Afghanistan) to northwest India, followed by the rise of the Iranian Yaz culture at 1500 BCE, and the Iranian migrations into Iran at c. 800 BCE. The highly evolved Harappan culture was followed by the arrival of a wave of nomadic tribes. The Aryans, as they are called, came from Central Asia and settled in the plains of the Indus and Ganges rivers. We know about the Aryan culture mainly through the Vedas, a collection of hymns that tells us about the life of the people, their gods, and the evolution of their society into a distinct caste system. The Vedas were composed in Sanskrit, and are still chanted in Hindu religious ceremonies. In the late Bronze Age and early Iron Age of the history of India when the Vedic literature, including the Vedas (c.1500–900 BCE), was composed in the northern Indian subcontinent, between the end of the urban Indus Valley Civilisation and a second urbanisation, which began in the central Indo-Gangetic Plain c.600 BCE. The Vedas contain details of life during this period that have been interpreted to be historical and constitute the primary sources for understanding the period. These documents, alongside the corresponding archaeological record, allow for the evolution of the Indo-Aryan and Vedic culture to be traced and inferred.